Rabbits, which are an important animal species used as lab animals, are mainly used for the purpose of research or authorization in various fields such as pharmacology, immunology, hematology, pathology, endocrinology, etc. In the reproductive toxicological respect, rabbits are used as a useful animal species for detecting the teratogenicity of drugs. For a female rabbit, a natural ovulation does not occur, but an ovulation is induced by mating stimulation of a male or hormone or electrical stimulation, and thus according to necessity, the mating time and the number of the mating animals can be controlled. In addition, since the size of the fetus of the female rabbit is comparatively larger than that of a rat or mouse, the female rabbit has an advantage that more exact observations can be made at the time of the morphological detection of the fetus (Gibson, J P, Staples, R E and Newberne, J W (1966): Use of rabbit in teratogenecity studies. Toxicol and Appl Pharmacol, 9:398-408). Because of these various advantages, the guidelines for toxicity tests of the U.S. Food and Drug Administration (FDA), Organization for Economic Cooperation and Development (OECD) and the National Institute of Safety Research also prescribe that rabbits must be used for the evaluation of the teratogenicity using non-rodents.
The teratogenicity test using rabbits requires numerous pregnant animals for a short time. There are two methods currently used for the above purpose: a natural mating method in which the female and male rabbits directly mate; and an artificial insemination method in which the semen ejaculated outside according to the natural mounting acts of the male rabbits is collected using an artificial vagina and the collected semen is injected into the female rabbit.
However, the natural mating method has the shortcoming that it needs much time and effort and requires numerous male animals. The artificial insemination of rabbits using the artificial vagina method has the problem that the time required for semen collection is very irregular according to the condition of the male rabbit; the semen ejaculation and collection rates are very low; and the failure probability is high due to impurities such as urine. In addition, since the artificial insemination method requires a great quantity of unnecessary male rabbits for inducing the mounting act, it is very inefficient in terms of facilities maintenance and breeding space utilization.
Meanwhile, the collection of semen is first required for the artificial insemination of animals. For the semen collection causing ejaculation by artificially stimulating the ejaculation center, various methods are used according to the species of the animals, for example, a massage method, an electrical stimulation method, a hydraulic pressure method, an artificial vagina method, etc.
The massage method, which is mainly used for turkeys or cocks, is to, in the case of cocks, turn their heads upside down and, after a massage between the pubis and the carina, push the basal part of the degenerated copulatory organ, thereby collecting the leaked semen.
The electrical stimulation method, which is used for pigs, cows, sheep, dogs, etc., is to apply electrical stimulation to the sacrum part to excite the ejaculation center, thereby collecting semen.
The hydraulic pressure method, which is mainly used in pigs, is to stimulate the sexual appetite of pigs and mount the dummy and apply pressure by hand at the moment when the penis comes out, thereby having the pigs ejaculate.
The artificial vagina method, which is mainly used for cows, horses, sheep and rabbits and is partially used for pigs, is to have ejaculation occur within the artificial vagina by using an artificially-made vagina which has temperature and pressure conditions similar to the reproductive organs of animals.
Meanwhile, since minute blood vessels are complicatedly entangled within the vas deferens and the epididymis, if the semen is collected by inserting a catheter directly into the above vas deferens and epididymis, there is a problem that the semen and the blood are mixed and thus pure semen cannot be obtained.
Accordingly, the inventors of the present invention studied a new artificial insemination method and semen collection method which will improve the problems of the conventional method of artificial insemination of lab animals, thereby completing the present invention regarding a method of collecting semen from the epididymis or the testis of a lab animal and an artificial insemination method using it, which is excellent in terms of the pregnancy rate and productivity; is time-efficient; and is superior in economic and industrial respects by preventing a huge economic loss due to the costs for maintaining the mass breeding of animals.